1. Field of the Invention
The present invention relates to a device for absorbing shocks and thereby reducing the noise that occurs during the feeding of sheets from a sheet feeding device into an electrophotographic apparatus and, more specifically, to a sheet feeding device that uses an air damper to reduce the noise and vibration generated during operation of the sheet feeding device.
2. Background Art
An image formation apparatus (e.g., a printer, scanner, facsimile or copier) must often accommodate printable mediums having a thickness or dimensions different from that of standard paper. Envelopes, postcards, transparencies, labels and resume paper are just a few examples of the different printable mediums that a sheet feeder must accommodate. A sheet feeder may be constructed to use a tray that supplies paper to a printer. The tray often has an adjustment lever allowing the paper to be moved away from a pickup roller in order to load additional sheets of paper into the tray. After loading additional paper, the adjustment lever is moved in a direction opposite that used for preparing the tray to receive additional paper causing the pickup roller to press against the paper on the tray and then transfer the paper to a transfer roller. Then, the transfer roller transports the sheet of paper to the printer cartridge.
Electrophotographic devices tend to use pick-up rollers to remove sheets from the sheet feeding device. However, when the tray is brought into contact with the pick-up roller a shock occurs due to the force provided by an elastic member to the tray. Some conventional devices use cams to gently move the tray up and down throughout the sheet feeding process. Such a process, however, often results in a lack of precision in the sheet feeding operation as the pick-up roller must load the paper before the cam finishes a predetermined portion of the cam's rotation.
As such, I believe that it may be possible to improve on the contemporary art by providing a sheet feeding device that reduces the vibration created by loading sheets, does not require the use of a cam, does not undergo greater vibration when a lesser amount of paper is stored on the tray, and that is economical to manufacture.